I've installed this filter three days ago and I'm already seeing results from it. The acceleration response is faster than before, the car seems to be breathing easier now. My fiat is a 69hp automatic pop version, but it feels like I get more out of the engine than before. I'm very happy with this filter, because my country has very strict regulations regarding the modification of your own vehicle. The one thing that I'm missing, is the better sound of the car. It might be, that you have to install a different exhaust other than the stock to hear the difference. The negative thing about the filter is the smell when you first install it and start up the engine. I noticed that it somehow smelled like something burned, it might have been due to the fact that the filter is very oily at the beginning, but after a couple of kilometers/miles, the smell disappeared. I would like to recommend this product to everybody, who likes to take care of their car, improve the engine performance and reduce fuel consumption.